| 摘要 |
PURPOSE:To enable overlap printing of dots to be performed in the same period as that for normal printing by providing, in addition to a normal head, a small-diameter head smaller in orifice diameter than the normal head, end printing dots by the small- diameter head in the manner of overlapping with the dots printed by the normal head, thereby enhancing printed density. CONSTITUTION:A head 6 comprises, in combination, a normal head 12 comprising a vertical row of a plurality of standard-diameter orifices 11 and a small-diameter head 14 comprising a vertical row of a plurality of orifices 13 which are smaller in diameter than the orifices 11. The small diameter head 14 is disposed adjacent to and on the rearward side of the normal head 12 with respect to a printing direction P. A main controlling part 20 is so connected that data can be transferred thereto from a host such as a word processor, and is so connected that detection signal can be inputted thereto from verious sensors 27. Based on various instruction signals, the main controlling part 20 controls a sheet-feeding motor 29, and drives the normal head 12 and the small-diameter head 14, which constitute the head 6, through driving circuits 31, 32. Therefore, it is possible to appropriately control the quantity of an ink even in the case of overlap printing of dots for enhancing printed density at the time of emphasizing characters or of high-speed draft printing. |
